diff --git a/package.json b/package.json
index 37de270949..696e616fce 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "openlayers",
-  "version": "5.0.0-beta.12",
+  "version": "5.0.0-beta.14",
   "description": "Build tools and sources for developing OpenLayers based mapping applications",
   "keywords": [
     "map",
@@ -16,8 +16,10 @@
     "serve-examples": "mkdir -p build/examples && webpack --config examples/webpack/config.js --mode development --watch & serve build/examples",
     "build-examples": "webpack --config examples/webpack/config.js --mode production",
     "build-index": "node tasks/generate-index",
-    "prebuild": "npm run build-index",
-    "build": "rollup --config config/rollup.js",
+    "set-version": "node tasks/set-version",
+    "prebuild": "npm run set-version && npm run build-index",
+    "prepare": "npm run set-version",
+    "build": "rollup --config config/rollup.js && cleancss --source-map src/ol/ol.css -o build/ol.css",
     "presrc-closure": "npm run prebuild",
     "src-closure": "node tasks/transform-types",
     "pretypecheck": "npm run src-closure",
diff --git a/src/ol/AssertionError.js b/src/ol/AssertionError.js
index ba70e8a492..1510800b98 100644
--- a/src/ol/AssertionError.js
+++ b/src/ol/AssertionError.js
@@ -13,7 +13,7 @@ import {VERSION, inherits} from './index.js';
  */
 const AssertionError = function(code) {
 
-  const path = VERSION ? VERSION.split('-')[0] : 'latest';
+  const path = VERSION.split('-')[0];
 
   /**
    * @type {string}
diff --git a/src/ol/index.js b/src/ol/index.js
index 0e289d3923..330e73fdf5 100644
--- a/src/ol/index.js
+++ b/src/ol/index.js
@@ -68,7 +68,7 @@ export {HAS_WEBGL, WEBGL_MAX_TEXTURE_SIZE, WEBGL_EXTENSIONS};
  * OpenLayers version.
  * @type {string}
  */
-export const VERSION = 'v4.6.4';
+export const VERSION = '5.0.0-beta.14';
 
 
 /**
diff --git a/tasks/set-version.js b/tasks/set-version.js
new file mode 100644
index 0000000000..004f8bb9ec
--- /dev/null
+++ b/tasks/set-version.js
@@ -0,0 +1,23 @@
+const fs = require('fs');
+const pkg = require('../package.json');
+
+const index = require.resolve('../src/ol/index');
+const lines = fs.readFileSync(index, 'utf-8').split('\n');
+
+const versionRegEx = /const VERSION = '(.*)';$/;
+
+for (let i = 0, ii = lines.length; i < ii; ++i) {
+  const line = lines[i];
+  if (versionRegEx.test(line)) {
+    lines[i] = line.replace(versionRegEx, `const VERSION = '${pkg.version}';`);
+    break;
+  }
+}
+
+const packageJson = require.resolve('../src/ol/package.json');
+const packageJsonObj = JSON.parse(fs.readFileSync(packageJson, 'utf-8'));
+packageJsonObj.version = pkg.version;
+fs.writeFileSync(packageJson, JSON.stringify(packageJsonObj, null, 2), 'utf-8');
+
+
+fs.writeFileSync(index, lines.join('\n'), 'utf-8');